Drag'n'Drop move on remote fails

When I try to drag'n'drop move files on my remote NAS, connected via SSH, from a local folder to an external device, usually an attached USB drive, the move fails with:

General failure (server should provide error description).
Error code: 4
Error message from server: Failure
Request code: 18

The move in this case was from /share/MD0_DATA/Qmultimedia/Films/* to /share/external/sdi

Moves within the same directories are fine, just to my USB drive fails.

The only way I can do it is to use a terminal session and issue a manual "mv" command: mv /share/MD0_DATA/Qmultimedia/Films/* /share/external/sdi/

Is there any way to get WinSCP, running v4.2.4 (build 610) to perform the move for me?

Your server probably does not support moving across filesystems.

martin wrote:

Your server probably does not support moving across filesystems.

When you say "server", do you mean the NAS or the SSH service? Also, the external USB is also formatted EXT3 like the main drive.

SSH/SFTP service.

martin wrote:

SSH/SFTP service.

Ok, so what function is it that's required by the service so I can ask the NAS company if it can be enabled or added?